There is consistent evidence showing that the prevalence of excess weight is increasing all over the world. In Canada, the prevalence is 59.4%, of which 23.1% can be ascribed to obesity and 36.0% to overweight. These proportions are higher in aboriginal populations,
along with higher prevalence of food insecurity and a transition diet characterized by less
traditional foods known to be of high nutrient content, and more market foods of lower
nutritional density. Because of this situation, the World Health Organization has
recommended new research strategies and initiatives in order to document the health status
of these populations and prevent negative health consequences.
Our study aimed to describe the phenomena of excess weight and food insecurity among
adult First Nations (FN), aged 19 years and over, living on the reserves of British Columbia
(BC); this sample is the first of a ten year project, the “First Nations Food, Nutrition and
Environment Study” (FNFNES) aiming to document the nutritional status and exposure to
contaminants in Canadian First Nations communities living south of the 60th parallel.
Specifically, this thesis aims to link three health dimensions: excess weight, diet quality and
food insecurity. We explored whether in the context of FN people living on the reserves of
BC, 1) an inadequate diet quality is associated with a higher risk of excess weight; 2)
household food insecurity is associated with inadequate diet quality; and 3) together, diet
quality and food insecurity might explain the high prevalence of excess weight.
Our results (from univariate, bivariate, MANOVA and logistic regression analysis of data
collected in 2008/2009) show that among women (n = 493) and men (n = 356) respectively,
the prevalences were 44.8% and 35.4% for obesity, and 31.6% and 41.3% for overweight,
for a total of 76.4% and 76.7% for excess weight; for food insecurity, the prevalence was
39.3% for women and 34.8% for men. Only 42.4% of women and 43.8% of men had
sufficient access to traditional foods. After controlling for sociodemographic and lifestyle
variables, the results of multivariate analysis suggest that although the prevalences of
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excess weight and food insecurity were similar between genders, the process linking excess
weight, diet quality and food insecurity was different among men and women. Indeed, in
women, the excess weight might be explained by compromised diet quality, as observed
through relatively high energy intakes (OR = 2.26; 95% CI: 1.13 - 4.52), more frequent
consumption of carbonated beverages (OR = 2.70; CI: 1.11- 6.56 for overweight and OR =
2.53; CI: 1.05 - 6.09 for obesity), together with physical inactivity (OR = 0.52; CI: 0.28 -
0.58 for the moderate physical activity group and OR = 0.36; CI: 0.18 - 0.72 for the active
group). Cereals (OR = 0.35; CI: 0.16- 0.75) and dairy products (OR = 0.40; CI: 0.16 - 0.95)
played a protective role against excess weight. Moreover, household food insecurity
influenced diet quality (through saturated fatty acids, p = 0.02) but when the three variables
were analysed together, the only dimension associated with excess weight in women was
diet quality, but not food insecurity. In men, the only dietary factor associated with excess
weight was white bread, in a paradoxically protective role (OR = 0.38; CI: 0.18-0.76 for
overweight and OR= 0.36; CI: 0.16-0.80 for obesity); also, when the three variables were
put together, food insecurity played a protective role for excess weight, in the context of
relatively high rate of smoking, also known to be protective of excess weight, which cannot
help explain the high prevalence of excess weight in men living on the reserves of BC.
More detailed studies, carried out in larger samples, would be necessary to better
understand these relationships. This study already suggests that positive effects on the
reduction of excess weight could result from policies and programmes aiming to reduce
carbonated drink intakes and physical inactivity, and to encourage consumption of cereals
and dairy products, especially in women. Regarding men, our results do not permit specific
recommendations. However, healthy behaviours recommended for women might be
extended to men, while waiting for results from further studies.